1. Half a Heart
Partial artificial hearts attach to the top half of a damaged heart to improve the organ's function. Surgeons cut away the bottom half of the heart, or the atria, and stitch the plastic replacement part directly onto the remaining top section of the heart. A partial artificial heart, made by SynCardia Systems, replaces two damaged ventricles, or the chambers that pump blood throughout the body. Only patients with both ventricles nonworking are candidates for the device.
2. Buying Time With an Artificial Heart
Health care professionals use artificial hearts as bridges to heart transplants. While the patient waits for a donated heart to use in a transplant, an artificial heart keeps the patient alive longer than a damaged heart can. The artificial heart can improve a patient's blood function and make the patient an even better candidate for the heart transplant. Almost half of those patients who annually wait for a heart transplant never receive one since donor heart demand is higher than supply. Artificial hearts can increase a patient's chances of receiving a heart by prolonging life until a donor heart becomes available.
3. Forcing the Blood Throughout the Body
The partial artificial heart uses a device about the size of a washing machine to monitor and control its function. This large fan generates air to force the blood that fills half of each of the ventricle replacement chambers to the lungs and other parts of the body. The air reaches these chambers through tubes that connect from the patient's chest to the fan mechanism. Researchers continue to investigate smaller, less bulky control devices to manage the artificial heart functions.
4. Artificial Heart Transplant Candidates
Candidates for an artificial heart transplant include patients who suffer from biventricular heart failure, or patients with severe damage to both chambers of the heart. Even at rest, these patients are short of breath, suffer from an increased heart rate, feel fatigued and suffer from swollen tissue as a result of slowed blood flow throughout the body, causing a buildup of fluid in the tissues. Artificial heart transplant candidates must have irreversible damage to the heart and must be in line for heart transplants.
5. Mechanical Heart Transplant
Abiomed, Incorporated developed a whole heart to replace damaged hearts in patients who are ineligible for donor heart transplants. This 2-lb. replacement device takes over for a patient's heart, which surgeons remove before implanting the artificial heart. The artificial heart runs on battery power with an internal and external power source. When a patient sleeps, the control unit to the artificial heart can plug directly into an outlet while batteries recharge. Whole artificial hearts can prolong life anywhere from 10 to 17 months.
